Onion smart home

Hey guys, I want to use a few onion omegas to create a smart house. I want to do an Omega per sub systems (sprinkler, lights, hvac, etc) and they all pull into a centralized system. I'm thinking of something like a raspberry pi running a graphical interface that sends inputs to the omega. Have any of y'all done anything like this? Or do you all know where I can find more info on having an Omega communicate in this way (system -> subsystem -> output)?

System:
Use Mqtt for the communication between your omegas. I would setup the raspberry as the broker.SubSystem:
Read your device with the omega send the information to the raspberry via mqtt.Output:
Display all Topics form the mqtt broker on the Raspberry.